[PATCH 05/17] i2c: omap: split out [XR]DR and [XR]RDY

Felipe Balbi
2012-06-14T10:20:38Z

While they do pretty much the same thing, there
are a few peculiarities. Specially WRT erratas,
it's best to split those out and re-factor the
read/write loop to another function which both
cases call.

This last part will be done on another patch.

While at that, also avoid an unncessary register
read since dev->fifo_len will always contain the
correct amount of data to be transferred.

Signed-off-by: Felipe Balbi <balbi@ti.com>
---
drivers/i2c/busses/i2c-omap.c | 126 ++++++++++++++++++++++++++++++-----------
1 file changed, 92 insertions(+), 34 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index fa9ddb6..0661ca1 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -844,36 +844,62 @@ complete:
return IRQ_HANDLED;
}

- if (stat & (OMAP_I2C_STAT_RRDY | OMAP_I2C_STAT_RDR)) {
+ if (stat & OMAP_I2C_STAT_RDR) {
u8 num_bytes = 1;

+ if (dev->fifo_size)
+ num_bytes = dev->fifo_size;
+
+ while (num_bytes--) {
+ if (!dev->buf_len) {
+ dev_err(dev->dev,
+ "RDR IRQ while no data"
+ " requested\n");
+ break;
+ }
+
+ w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
+ *dev->buf++ = w;
+ dev->buf_len--;
+
+ /*
+ * Data reg in 2430, omap3 and
+ * omap4 is 8 bit wide
+ */
+ if (dev->flags &
+ OMAP_I2C_FLAG_16BIT_DATA_REG) {
+ if (dev->buf_len) {
+ *dev->buf++ = w >> 8;
+ dev->buf_len--;
+ }
+ }
+ }
+
if (dev->errata & I2C_OMAP_ERRATA_I207)
i2c_omap_errata_i207(dev, stat);

- if (dev->fifo_size) {
- if (stat & OMAP_I2C_STAT_RRDY)
- num_bytes = dev->fifo_size;
- else /* read RXSTAT on RDR interrupt */
- num_bytes = (omap_i2c_read_reg(dev,
- OMAP_I2C_BUFSTAT_REG)
- >> 8) & 0x3F;
- }
+ omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RDR);
+ continue;
+ }
+
+ if (stat & OMAP_I2C_STAT_RRDY) {
+ u8 num_bytes = 1;
+
+ if (dev->fifo_size)
+ num_bytes = dev->fifo_size;
+
while (num_bytes--) {
if (!dev->buf_len) {
- if (stat & OMAP_I2C_STAT_RRDY)
- dev_err(dev->dev,
+ dev_err(dev->dev,
"RRDY IRQ while no data"
- " requested\n");
- if (stat & OMAP_I2C_STAT_RDR)
- dev_err(dev->dev,
- "RDR IRQ while no data"
- " requested\n");
+ " requested\n");
break;
}

w = omap_i2c_read_reg(dev, OMAP_I2C_DATA_REG);
*dev->buf++ = w;
dev->buf_len--;
+
/*
* Data reg in 2430, omap3 and
* omap4 is 8 bit wide
@@ -886,36 +912,68 @@ complete:
}
}
}
- omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_RRDY |
- OMAP_I2C_STAT_RDR));
+
+ omap_i2c_ack_stat(dev, OMAP_I2C_STAT_RRDY);
continue;
}

- if (stat & (OMAP_I2C_STAT_XRDY | OMAP_I2C_STAT_XDR)) {
+ if (stat & OMAP_I2C_STAT_XDR) {
u8 num_bytes = 1;
- if (dev->fifo_size) {
- if (stat & OMAP_I2C_STAT_XRDY)
- num_bytes = dev->fifo_size;
- else /* read TXSTAT on XDR interrupt */
- num_bytes = omap_i2c_read_reg(dev,
- OMAP_I2C_BUFSTAT_REG)
- & 0x3F;
+
+ if (dev->fifo_size)
+ num_bytes = dev->fifo_size;
+
+ while (num_bytes--) {
+ if (!dev->buf_len) {
+ dev_err(dev->dev,
+ "XDR IRQ while no "
+ "data to send\n");
+ break;
+ }
+
+ w = *dev->buf++;
+ dev->buf_len--;
+
+ /*
+ * Data reg in 2430, omap3 and
+ * omap4 is 8 bit wide
+ */
+ if (dev->flags &
+ OMAP_I2C_FLAG_16BIT_DATA_REG) {
+ if (dev->buf_len) {
+ w |= *dev->buf++ << 8;
+ dev->buf_len--;
+ }
+ }
+
+ if ((dev->errata & I2C_OMAP3_1P153) &&
+ errata_omap3_1p153(dev, &stat, &err))
+ goto complete;
+
+ omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
}
+
+ omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XDR);
+ continue;
+ }
+
+ if (stat & OMAP_I2C_STAT_XRDY) {
+ u8 num_bytes = 1;
+
+ if (dev->fifo_size)
+ num_bytes = dev->fifo_size;
+
while (num_bytes--) {
if (!dev->buf_len) {
- if (stat & OMAP_I2C_STAT_XRDY)
- dev_err(dev->dev,
+ dev_err(dev->dev,
"XRDY IRQ while no "
"data to send\n");
- if (stat & OMAP_I2C_STAT_XDR)
- dev_err(dev->dev,
- "XDR IRQ while no "
- "data to send\n");
break;
}

w = *dev->buf++;
dev->buf_len--;
+
/*
* Data reg in 2430, omap3 and
* omap4 is 8 bit wide
@@ -934,8 +992,8 @@ complete:

omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
}
- omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
- OMAP_I2C_STAT_XDR));
+
+ omap_i2c_ack_stat(dev, OMAP_I2C_STAT_XRDY);
continue;
}

--
1.7.10.4